package com.hmdp.utils;


import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import java.io.InputStream;
import java.lang.reflect.Field;
import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;


public class ExcelUtil {

    private final static String excel2003L =".xls";    //2003- 版本的excel
    private final static String excel2007U =".xlsx";  //2007版本

    /**
     * @Description：获取IO流中的数据，组装成List<List<Object>>对象
     * @param in,fileName
     * @return
     * @throws
     */
    public static List<List<Object>> getListByExcel(InputStream in, String fileName) throws Exception{
        List<List<Object>> list = null;

        //创建Excel工作薄
        Workbook work = getWorkbook(in,fileName);
        if(null == work){
            throw new Exception("创建Excel工作薄为空！");
        }
        Sheet sheet = null;  //页数
        Row row = null;  //行数
        Cell cell = null;  //列数

        list = new ArrayList<List<Object>>();
        //遍历Excel中所有的sheet
        for (int i = 0; i < work.getNumberOfSheets(); i++) {
            sheet = work.getSheetAt(i);
            if(sheet==null){continue;}

            //遍历当前sheet中的所有行
            for (int j = sheet.getFirstRowNum(); j <= sheet.getLastRowNum(); j++) {
                row = sheet.getRow(j);
                if(row==null){continue;}

                //遍历所有的列
                List<Object> li = new ArrayList<Object>();
                for (int y = row.getFirstCellNum(); y < row.getLastCellNum(); y++) {
                    cell = row.getCell(y);
                    li.add(getValue(cell));
                }
                list.add(li);
            }
        }

        return list;

    }

    /**
     * @Description：根据文件后缀，自适应上传文件的版本
     * @param inStr,fileName
     * @return
     * @throws Exception
     */
    public static  Workbook getWorkbook(InputStream inStr,String fileName) throws Exception{
        Workbook wb = null;
        String fileType = fileName.substring(fileName.lastIndexOf("."));
        if(excel2003L.equals(fileType)){
            wb = new HSSFWorkbook(inStr);  //2003-
        }else if(excel2007U.equals(fileType)){
            wb = new XSSFWorkbook(inStr);  //2007+
        }else{
            throw new Exception("解析的文件格式有误！");
        }
        return wb;
    }

    /**
     * @Description：对表格中数值进行格式化
     * @param cell
     * @return
     */
    //解决excel类型问题，获得数值
    public static String getValue(Cell cell) {
        String value = "";
        if(null==cell){
            return value;
        }
        switch (cell.getCellType()) {
            //数值型
            case NUMERIC:
                if (DateUtil.isCellDateFormatted(cell)) {
                    //如果是date类型则 ，获取该cell的date值
                    Date date = DateUtil.getJavaDate(cell.getNumericCellValue());
                    SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
                    value = format.format(date);;
                }else {// 纯数字
                    BigDecimal big=new BigDecimal(cell.getNumericCellValue());
                    value = big.toString();
                    //解决1234.0  去掉后面的.0
                    if(null!=value&&!"".equals(value.trim())){
                        String[] item = value.split("[.]");
                        if(1<item.length&&"0".equals(item[1])){
                            value=item[0];
                        }
                    }
                }
                break;
            //字符串类型
            case STRING:
                value = cell.getStringCellValue();
                break;
            // 公式类型
            case FORMULA:
                //读公式计算值
                value = String.valueOf(cell.getNumericCellValue());
                if (value.equals("NaN")) {// 如果获取的数据值为非法值,则转换为获取字符串
                    value = cell.getStringCellValue();
                }
                break;
            // 布尔类型
            case BOOLEAN:
                value = " "+ cell.getBooleanCellValue();
                break;
            default:
                value = cell.getStringCellValue();
        }
        if("null".endsWith(value.trim())){
            value="";
        }
        return value;
    }

    /**
     * 用反射方法，获取列名，比较，为属性赋值
     * @param object
     * @param fieldName
     * @param val
     */
    public static void setFieldValueByFieldName(Object object, String fieldName, String val) {
        try {
            //通过反射获取所有实体类所有定义的方法,object为数据库实体类
            Field[] fields = object.getClass().getDeclaredFields();
            //遍历fields
            for (int i = 0; i < fields.length; i++) {
                Field field = fields[i];
                //读取注释，如@Excel(name = "科目")
                Excel annotation = field.getAnnotation(Excel.class);
                //因为private类型，所有要设置允许
                field.setAccessible(true);
                //annotation.name() 注解里的属性,如果annotation没写注解，读取原始名字如subject
                if(annotation == null){
                    if(fieldName.equals(field.getName())){
                        if(field.getType() == Integer.class){
                            field.set(object, Integer.valueOf(val));
                        }else if(field.getType() == Long.class){
                            field.set(object, Long.valueOf(val));
                        }else if (field.getType() == Date.class){
                            SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                            Date parse = simpleDateFormat.parse(val);
                            field.set(object,parse);
                        }else {
                            field.set(object, val);
                        }
                        return;
                    }
                }else {//设置了注解，并且表格里的Excel字段值和注解的name值相同，则为相应字段赋值
                    if(fieldName.equals(annotation.name())){
                        //进行类型判断，因为实体类中变量类型不同。
                        if(field.getType() == Integer.class){
                            field.set(object, Integer.valueOf(val.toString()));
                        }else if(field.getType() == Long.class){
                            field.set(object, Long.valueOf(val.toString()));
                        }else {
                            field.set(object, val);
                        }
                        return;
                    }
                }

            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }
}

